Can action strip converted back to keyframes?
The action editor and the graph editor both allows us to edit the active action of an object, only one action can be active for an object at any given time. When an action is added to the NLA editor it is unlinked from being the active action for the object.

While an action is removed as the active action for the object, it is still an action which contains the same editable keyframes and f-curve data, it can be edited again at a later time by making it the active action again. This can be done by selecting it in the action editor when the object is selected.



You will also find that it can also be associated with a different object and added to the NLA for both objects allowing both to be animated the same with the timing being offset for each object if desired.